1. Field of the Invention
The present invention relates to an information processing apparatus that is capable of autonomously controlling supply of electric power inside the apparatus and a memory managing program and a memory managing method for the information processing apparatus.
2. Description of the Related Art
In recent years, in the field of the computer system technology, power control techniques for reducing power consumption at standby time by stopping supply of electric power inside an apparatus when processing is not performed and resuming the supply of electric power instantaneously when processing is required, for example, when input operation is applied to the apparatus have been developed.
In addition, in recent years, non-volatile memories such as a Ferroelectric Random Access Memory (FeRAM) and a Magneto-resistive Random Access Memory (MRAM) have been developed. Such non-volatile memories do not require electric power for maintaining storage of information. Thus, for example, even when the power control described above is performed and supply of electric power to the memory is stopped, information, which is stored before the supply of electric power is stopped, is held on the memory.
Since it is possible to access such non-volatile memories at high speed, it is expected that the non-volatile memories are used as general-purpose memories in computer systems.
Incidentally, in the conventional software techniques, as in the power control techniques described above, it is not assumed in principle that processing is resumed after power supply to a computer is suspended temporarily. In restarting the computer, in general, operating system software (OS) performs start involving initialization of a system (so-called cold start).
Note that, concerning the power control for the computer systems, for example, JP9-114557A discloses a technique such as suspend or resume.
However, in the conventional computer systems, when the memory is managed, a method of managing a starting address of an area in use on the memory and, in allocating or releasing the memory, designating the starting address of the area is used.
Therefore, even when the non-volatile memories such as the FeRAM and the MRAM are used, when supply of power is suspended as described above and the supply of power is resumed as required by processing, there is a problem in that management information of a memory address is lost and the information stored on the memory cannot be accessed as the OS performs the cold start.
When the OS performs the processing such as suspend or resume, the management information of the memory address is stored in a storage such as a hard disk. Thus, it is possible to access the information on the memory even when the power supply of the computer is turned on again.
However, the conventional processing such as suspend or resume is not processing that assumes use of a non-volatile memory. There is a problem in that it is necessary to save a large quantity of information in the memory or the hard disk in executing the processing and, when the power supply of the computer is turned on again, the information does not surely return to an original state in some cases.